Water shutoff for oil wells



Aug. 31, 1948. i c. E. ASHTON 2, 48,

1 WATER SHU-TOFF FOR OIL wnms Filed Aug; 16, 1944 2 Sheets-Sheet 1 Fig.1

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Charles Edwin flsblon Aug. 31, 1948. c. E. ASHTON 2,448,205

WATER ISHUTOFF FOR 011. WELLS Filed Aug. 16, 1944 -2 Sheets-Sheet 2 Patented Aug. 31, 1948 i.) N I T ED S TAT ES .LPATENT. O-F-F.ICE

WATER SHUTOFF FOR OIL WELLS Gharles Edwin Ashton, Stockton, Calif.

Application August 16, 1944, Serial No. 549,725

4 Claims.

. tions andpart'icularly to the sealing off of water which is almost always present in variou underground strata, and which must be prevented from entering the well not only while it is being drilled, but subsequently.

At present, this is done by cementingan operation which takes considerable time, and the expenditure and loss of manpower, both in doing the job and in waiting for the cement to set, before drilling operations can be resumed.

The principal purposes of my invention are to eliminate the above objectionable features of present operation by providing a water sealing device which instantly shuts oil the water, which requires but little time to place in operation so that the drilling may be quickly resumed, and which effects a considerable SaVing in expense, time and manpower over present methods.

A further object of the invention is to produce a simple and inexpensive device and yet one which will be exceedingly effective for the purpose for which it is designed.

These objects I accomplish by means of such structure and relative arrangement of parts as will fully appear by a perusal of the following specification and claims.

In the drawings similar characters of reference indicate corresponding parts in the several views:

Figure l is a sectional elevation of my improved water shut-ofi or sealing device as attached to a well casing and in the bottom of a well bore, but before becoming effective as a seal.

Figure 2 is a similar view showing the device in its sealing position.

Figure 3 is a top plan view of the device.

Referring now more particularly to the characters of reference on the drawings, I denotes the bore of a partly drilled well, a derrick-supported casing 2, of smaller diameter than the bore, depending into the same as is customary in well drilling operations,

My improved water shut-off or sealing device is mounted on and suspended from a string of casing and comprises a coupling collar 3 screwed onto the lower end of the casing. Suitably secured on and depending from the collar is a substantially .cylindrical band 4 of thick resilient rubber or similar cushioning or sealing material which at its lower end, is secured in a rigid and somewhat heavy ring 5, whose bore is greater than that of the casing 2. The band 4 extends below the ring 5 and underlaps the same to form an endless resilient base and sealing bead 6.

The ring 5 is guided for vertical movement relative to the collar 3 by circumferentially spaced rods 1 projecting upwardly from the ring 5, and slidably extending through upwardly flaring holes 8 in the collar, and which in the bottom snugly fit the rods. The flare of the holes allows of a certain amount of tilting of the ring 5 and the attached band 4, as the level of the bottom surface 9 of the Well may necessitate.

In operation before the casing is lowered into the well, the sealing device is secured on the lower casing section by screwing the collar 3 thereon. As long as the casing is held suspended so that the bead is not in contact with any flat surface, the band 4 will remain relatively straight. Said band, however, is intentionally and initially formed between the collar and ring with a slight bulge as shown in Figure 1, in order to facilitate outward buckling thereof. As soon as the bead 6 strikes the bottom of the well bore, the weight of the casing, it still being lowered, causes the sealing band to buckle outwardly until it forms a substantially horizonta1 double-thickness annular flange Ill, which engages the bore wall of the well as shown in Figure 2. The length of this buckling portion of the band relative to the radial width between the casing and the bore of th well, is such that the flange ill will then engage the bore wall with a proper sealing fit. In other words, the rubber is somewhat compressed where it enases the bore wall. At the same time the base head 6 also engages the bottom of the well with a sealing fit, since the weight of the casing is also pressing on said bead through the buckled sealing band,

As a result, the well within the casing is sealed off both at the bottom and all about the side, preventing water from entering the well and enabling drilling operations to be instantly resumed. Such operations are, of course, carried on with a smaller drill bit, leaving the sealing device supported on the shoulder or ledge left by the smaller bit. When the well is completed, earth will gradually se-ttle onto the sealing flange It, making the seal permanent.

If the well gives out, the casing may be withdrawn and used again, since it is not cemented in place. Here again, a large saving in expense is effected.

From the foregoing description it will be readily seen that I have produced such a device as substantially fulfills the objects of the invention as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appending claims.

Having .thus described my invention, What I claim as, new and useful and desire to secure by Letters Patent is:

1. A water sealing device for a Well-bore having a casing therein of smaller diameter than the bore, said device comprising a collar adapted to be secured on the lower end of the casing, a band of flexible resilient sealing material depending from the collar and formed with an initial outward bulge, a rigid ring in the band at its lower end, and a base bead formed with the band and,

3. A device as in claim 1, with rods upstanding from the ring and slid-ably projecting through the collar.

4; A water sealing device for a Well bore having a casin therein of smaller diameter than the bore; said device comprising a collar secured on the lower end of the casing, an annular band of flexible and resilient sealing material secured on and depending from the outside of the collar, a rigid ring fixed in the band at its lower end and spaced from the collar, the band being arranged to flex outwardly and seal against the wall of the bore when the ring rests on the bottom of the bore and the weight of the casing bears against the band, and guide rods upstanding from the ring: the collar having upwardly flaring guide holes for the rods.

CHARLES EDWIN ASHTON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

